It's not the first time I see physics researchers criticise others fields for not being as strict as theirs. They usually have a tendency to oversimplify the other fields without taking in consideration practical factors such as the impossibility to obtain large samples or repeat an experiment many times in the exact same conditions.

Are you really having this argument ? It is obvious that we won't build a rail track on every road but at the same time denying that taxes will shitft some cargo towards trains and create new rail tracks does not make any sense !

This is because you associate capitalism with evil: in many cases debt can be a useful tool. For a rich entrepreneur it can allow to diversify his exposure to a single business without realising the capital gain tax for example. For people with good ideas, it allow to allocate the capital to something with a higher return on investment. This is why finance is actually useful, it allows some allocation of money more efficiently than if you tried to do it with a single entity which becomes invariable corrupt. The post above my previous reply is totally oblivious to the fact that many of the recent changes in the last centuries are probably more due to modern economy and liberalism allowing the economy to flourish and scientific progress to be made.

I take it you don't take your own advice, you would have noticed that without being invested in stocks for long periods of time you would lost much to inflation. A better solution is to use defensive stocks.